Fancy coffee is usually made through adding milk foams in coffee liquid. According to a steam foaming nozzle device of a coffee maker with an application No. 201020575326.4 disclosed on Aug. 10, 2011, rotating to adjust a sleeve can change the indrawn air volume, so as to adjust the fine degree of the milk foams. Moreover, the steam temperature usually needed to make the milk foams is higher than the temperature for extracting coffee liquid, and a liquid heating system with a reasonable structure will make the fancy coffee maker be more energy-saving, and efficient.